# 这是一行注释
# """
# a = 10
# print('hello')
# """
#
# # print(1+3)
# # 17 , 23 , 34 , 56求其方差
# '''
# avg = (17+23+34+56) / 4
# num = 4
# total = (17-avg) ** 2 + (23-avg) ** 2 + (34-avg) ** 2 + (56-avg) ** 2
# result = total / (num-1)
#
# print(result)
# '''
#
# a = 10
# print(type(a))
#
# a = 3.14
# print(type(a))
#
# a = "learning python"
# print(a)
#
# b = len(a)
# print(b)

# a = True
# print(type(a))
#
# a = False
# print(type(a))

# 注释是CTRL + /

# a = 3.14
# print (a)
# print("\n")
# print(type(a))

#字符串可以和字符串相加
# a = "hello"
# b = " world !"
# print(a+b)

#在python中变量都是动态变量会随着编译的进行而改变

# a:int = 10
#
# b:float = 3.14
# b = 10
# print(b)
# print(type(b))

# a = "'hello world' is a simple string"
# b = '''my 'name' "is zjy"'''
# print(a)
# print(b)

# #相加不可以字符串和数字相加
# # a = ("abcdef")
# b = 3
# # print(a+b)
#
# c = 3.14
# print(b+c)